--%>

Problem on work of compression

A diesel engine operates devoid of a spark plug by using the high-temperature gas produced throughout the compression stage to ignite the fuel. During a typical compression, pure air that is originally at 21 °C and 0.95 bar is reversibly and adiabatically compressed to 1/20 of its original(actual) volume by the piston, as shown in the figure below.

a) If air is assumed to obey the ideal gas equation of state, find out the pressure and temperature in the cylinder at the end of the compression. The constant-pressure heat capacity of air varies with temperature and is given by

Cp/R = 3.3 + 6x10-4

b) What is the work of compression in J/mol of air?

c) Is the ideal gas law a good approximation in this case? Why?

2455_ideal gas law.jpg

   Related Questions in Mechanical Engineering

  • Q : Carburetion A carburetor's primary

    A carburetor's primary function is to mix proper proportions is?

  • Q : Stop cooling-water flow in turbine

    Whether you stop cooling-water flow through steam condenser when the turbine is slopped?

  • Q : Brazing and Welding Differentiate the

    Differentiate the term Brazing and Welding?

  • Q : What is cotter joint Explain what is

    Explain what is meant by the Cotter joint?

  • Q : Calculating liquid composition There

    There is a 35% MeOH/water mix to feed to a flash at 100 Ib- mole /hr and 1 atm. We want a vapour composition of 60 % MeOH. What does the vapour flow rate need to be? What is the liquid composition? Give the equation of the operation line?

    Q : Causes and consequences of dynamic

    Discuss the causes and consequences of dynamic loading on structures based on two real examples. Support your discussion with proper diagrams or sketches. Your discussion shall include the time and location of the event, type and source of dynamic loa

  • Q : Problem on turbulent flow The

    The approximate equation for the velocity distribution in a rectangular channel with the turbulent flow is 655_turbulent flow.jpg

    Q : Measuring the Temperature in Wet Bulb

    Explain phenomenon to measure the Temperature in Wet Bulb Thermometer?

  • Q : Problem on mechanical efficiency of the

    The oil pump is drawing 25 kW of electric power while pumping oil with ρ = 860 kg/m3 at a rate of 0.1 m3/s. The inlet and outlet diameters of the pipe are of 8 cm and 12 cm, respectively. When the pressure rise of oil in the pump is measured to be 250 k

  • Q : Define spinning jenny Spinning jenny:

    Spinning jenny: It is a multi-spool spinning wheel. It was invented in the year 1764 by James Hargreaves in Stanhill, close to Blackburn, Lancashire in the north west of England (though Thomas Highs is another candidate recognized as inventor).